A Serpent in the course of its wanderings came into an
armourer’s shop. As he glided over the floor he felt his
skin pricked by a file lying there. In a rage he turned
round upon it and tried to dart his fangs into it; but he
could do no harm to heavy iron and had soon to give over
his wrath.
Moral Lesson: It is useless attacking the insensible.
―
Aesop